1 //===-- Condition.cpp -------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include <errno.h> 11 12 #include "lldb/Host/Condition.h" 13 #include "lldb/Host/TimeValue.h" 14 15 16 using namespace lldb_private; 17 18 //---------------------------------------------------------------------- 19 // Default constructor 20 // 21 // The default constructor will initialize a new pthread condition 22 // and maintain the condition in the object state. 23 //---------------------------------------------------------------------- 24 Condition::Condition () : 25 m_condition() 26 { 27 ::pthread_cond_init (&m_condition, NULL); 28 } 29 30 //---------------------------------------------------------------------- 31 // Destructor 32 // 33 // Destroys the pthread condition that the object owns. 34 //---------------------------------------------------------------------- 35 Condition::~Condition () 36 { 37 ::pthread_cond_destroy (&m_condition); 38 } 39 40 //---------------------------------------------------------------------- 41 // Unblock all threads waiting for a condition variable 42 //---------------------------------------------------------------------- 43 int 44 Condition::Broadcast () 45 { 46 return ::pthread_cond_broadcast (&m_condition); 47 } 48 49 //---------------------------------------------------------------------- 50 // Get accessor to the pthread condition object 51 //---------------------------------------------------------------------- 52 pthread_cond_t * 53 Condition::GetCondition () 54 { 55 return &m_condition; 56 } 57 58 //---------------------------------------------------------------------- 59 // Unblocks one thread waiting for the condition variable 60 //---------------------------------------------------------------------- 61 int 62 Condition::Signal () 63 { 64 return ::pthread_cond_signal (&m_condition); 65 } 66 67 //---------------------------------------------------------------------- 68 // The Wait() function atomically blocks the current thread 69 // waiting on the owned condition variable, and unblocks the mutex 70 // specified by "mutex". The waiting thread unblocks only after 71 // another thread calls Signal(), or Broadcast() with the same 72 // condition variable, or if "abstime" is valid (non-NULL) this 73 // function will return when the system time reaches the time 74 // specified in "abstime". If "abstime" is NULL this function will 75 // wait for an infinite amount of time for the condition variable 76 // to be signaled or broadcasted. 77 // 78 // The current thread re-acquires the lock on "mutex". 79 //---------------------------------------------------------------------- 80 int 81 Condition::Wait (Mutex &mutex, const TimeValue *abstime, bool *timed_out) 82 { 83 int err = 0; 84 do 85 { 86 if (abstime && abstime->IsValid()) 87 { 88 struct timespec abstime_ts = abstime->GetAsTimeSpec(); 89 err = ::pthread_cond_timedwait (&m_condition, mutex.GetMutex(), &abstime_ts); 90 } 91 else 92 err = ::pthread_cond_wait (&m_condition, mutex.GetMutex()); 93 } while (err == EINTR); 94 95 if (timed_out != NULL) 96 { 97 if (err == ETIMEDOUT) 98 *timed_out = true; 99 else 100 *timed_out = false; 101 } 102 103 104 return err; 105 } 106 107
